应用数学专业中英文翻译精选.docVIP

上海电力学院 本科毕业设计（英文翻译） 英文原文： Estimations For A Simple Step-Stress Model With Progressively Type-II Censored Data 院　　系：　 能源与环境工程学院　 　 专业年级：　 机械设计制造及其自动化2008级 学生姓名：　 杨晓晨　 学号：　 2012年5月12日 International Journal of Reliability, Quality and Safety Engineering Vol.12, No.5(2005) 385–395 ?World Scienti?c Publishing Company ESTIMATIONS FOR A SIMPLE STEP-STRESS MODEL WITH PROGRESSIVELY TYPE-II CENSORED DATA SHUO-JYE WU? and HSIU-MEI LEE Department of Statistics, Tamkang University Tamsui, Taipei 251 Taiwan ?shuo@stat.tku.edu.tw DAR-HSIN CHEN Graduate Institute of Finance National Chiao Tung University Hsinchu City 300, Taiwan Received 1 January 2005 Revised 23 May 2005 With today’s high technology, some life tests result in no or very few failures by the end of test. In such cases, an approach is to do life test at higher-than-usual stress conditions in order to obtain failures quickly. This study discusses the point and interval estimations of parameters on the simple step-stress model in accelerated life testing with progressive type II censoring. An exponential failure time distribution with mean life that is a log-linear function of stress and a cumulative exposure model are considered. We derive the maximum likelihood estimators of the model parameters. Confidenc eintervals for the model parameters are established by using pivotal quantity and can be applied to any sample size. A numerical example is investigated to illustrate the proposed methods. Keywords: Accelerated life test; confidence interval; exponential distribution; maximum likelihood method; pivotal quantity; progressive type II censoring. Introduction Accelerated life test (ALT) is often used for reliability analysis. Test units are run at higher-than-usual stress conditions in order to obtain failures quickly. A model relating life length to stress is fitted to the accelerated failure times and th